Bu php kodunda hatalı olan yer neresi?

<?php  

function IP_adresi_alma()
{
if (!empty($_SERVER['HTTP_CLIENT_İP']))
{
$IP = $_SERVER['HTTP_CLIENT_İP'];
}
elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
$IP = $_SERVER['HTTP_X_FORWARDED_FOR'];
}
else{
$IP = $_SERVER['REMOTE_ADDR'];
}
return $IP;
}

echo IP_adresi_alma();

<?php

function ip_adresi_alma()
{
if (!empty($_SERVER['HTTP_CLIENT_IP']))
{
$ip = $_SERVER['HTTP_CLIENT_IP'];
}
elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
$ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
}
else{
$ip = $_SERVER['REMOTE_ADDR'];
}
return $ip;
}
?>

<h1><i class="fas fa-map-marker-alt"></i>IP Adresim: <b>
<?php echo ip_adresi_alma(); ?>
</b></h1>